Burner for lighting gas and other combustible gases



J. SCHAFER July 4, 1950 BURNER FOR LIGHTING GAS AND OTHER COMBUSTIBLE GASES 2 Sheets-Sheet 1 Filed May 9, 1947 y 1950 J. scHAFER 2,513,523

BURNER FOR LIGHTING GAS AND OTHER COMBUSTIBLE GASES 2 Sheets-Sheet 2 llllll I Flled May 9 1947 Patented 'July 4, 1950 BURNER FOR LIGHTING GAS AND OTHER COIVIBUSTIBLE GASES Jean Schfifer, Paris, France Application May 9, 1947, Serial No. 746,913 In France July 19, 1941 Section 1, Public Law 690, August 8, 1946 Patent expires July 19, 1961 3 Claims. (01. its-27.4)

The object of the present invention is an improved burner device for illuminating gas and all other combustible gases giving with air an explosive mixture.

The present burner is made, preferably, to be used in the manner of a blow-pipe, that is to say, in the form of a tubular burner which can be held in the hand, producing at the end a very hot flame, but it can be adapted and used as a fixed burner for stoves, furnaces, crucibles and kilns and heating apparatus of all kinds, its possibilities'of use being very vast, because of the high temperatures which it produces, temperatures incomparably higher than those obtained up to now at low pressures with the gases considered. By this invention, one can obtain, with illumination gas, under a low pressure ranging about 40 gr./cm. a flame the temperature of which is raised up to 1800 C. and above, permitting the fusion of a large number of metals and their autogenous welding, so that the apparatus replaces advantageonsly, in the case of these metals, the oxyhydrogen blow-pipe, the compressed air blow-pipe and the brazing or welding lamp.

The chief characteristic of the invention is the combination of an injector or gas jet with several diffusing and mixing members placed successively between the injector in question and the lighting end of the burner, in the interior of an envelope or case surrounding them concentrically, provided at the base with an air intake, these members being so established as to produce several successive difiusions or mixings of the combustible gas, by mechanical means and with the intervention of streams of air drawn through each of them by the central gaseous current and striking the gaseous streams and mixing closely with them.

The apparatus may also include to advantage, between the last diffusing and mixing member and the lighting orifice or burner nozzle, a static mixing memberoperating by contraction of the gaseous current.

Finally, between this mixing member and the above-mentioned lighting orifice there can be arranged a conformator or regulator giving the desired shape to the flame, in combination or not with a cap and the invention has in view, in particular, such a conformator comprising a central pipe, in Venturi form, and a crown of orifice or passages concentric to this central pipe and extending well around the part of the central pipe intermediate its ends and only at a part of its length.

which is mounted therein with a tight fit.

In order that the invention may be clearly understood and readily carried into effect, reference may be had to the accompanying drawings, on which:

Figure 1 is a longitudinal section of one embodiment, the rear part of the burner being broken away.

Figure 1a is a side elevation of the rear part of the burner. Figure 1b is a section along the line xa: of Figure 1.

Figures 2 and 3 show, on a large scale, in longitudinal section and end view, the detail of a diiiusing and mixing member.

Figure 4 shows separately a conformator for regulating or shaping the flame.

Figure 5 illustrates a modificationof Figure 1, and

Figure 6 is a longitudinal section of another modification.

Referring to the drawing shown by Figure 1, the apparatus comprises a handle I, provided with a neck portion 2 for connection with the source of combustible gas, and comprises conveniently, a tap 3, controlling the passage 6f the gas through the central tube 4 of the said handle I. At the inner end of this tube 4 is fitted an injector or gas nozzle 5 having a calibrated or1-' fice 6, prolonged by a tubing 1, provided with numerous radial slits 8; this constitutes a first diffusing or mixing member.

The nozzle 5-! is in the centre of a tubular body 9, of larger diameter provided with lateral apertures I!) for the admission of air controlled by a rotatably mounted casing II, also provided with slots, forming a valve for regulating the air necessary for diffusing or mixing with the gas and thecooling of the apparatus. The handle I carries the air-mixing casing II which surrounds the nozzle 5 and which fits onto the body 9. The body 9 which has an air and gas-tight fit on to handle I, can be formed, as shown on the drawing, so as to serve as a support of the nozzle 5, The body 9 receives, by screwing or otherwise, a tubularpart l2 forming the envelope of the diffusers.

In the interior of the tubular part I2 there is arranged concentrically the tubular body of a second diffuser l3 coaxially with which is arranged the nozzle 5'l already described. 'The inner end of the tube I3 communicates freely, around the nozzle 1, with the interior of the air admission chamber formed within the body 9, and with an annular passage 12a located between the members 12 and [3.

The tube I3 is mounted, for example, by means of a ring M which is provided with holes I and which is secured between a shoulder of the body 9 and the end of the tubular part I2.

The tubular difiuser I3 comprises, as one can see on Figure 2, a convergent cone [3a, then a divergent cone [3b, which is tangent or extends to the interior wall of-the envelope I2,-the wall of this cone [379 being provided with a large number trate into the diffuser cone I311 and there 'pene-* trate into the gaseous current, intimately :mixing with it. It will be advantageous, asv shown, to commence the slots I6 at the smallest diameter of the tube I3, namely, at the intersection of the cones I31; and I31).

Beyond the diffuser I3-I3b, in the interior of the envelope I2, therecan be arranged a static mixer I'I, operating-by contraction of the gaseous stream. Following-on this there is arranged a conformator or flame regulator I8, comprising a central pipe I9 and a crown of small circumferentially spaced channels 2fi-which, in combination with a cap 2 I will give the elongated flame shown by {Figure 1, or, used alone, will give the more tapered flame shown'on; Figure 4.

Instead of using the mixer Il, one can bend the envelope I2, betweenthe cone I31) Y, and th regulator I8, as shown in Figure 5. i .2

One understands that the firstdiifusion which is "eflected in the member I, transforms the gas into an explosive combustible mixture.

The speed of flow of this explosive combustible mixture into the pipe I3 is determined by:

a. The section ofthe opening 6 of the nozzle;

b. The number and the section of the slits 8 of penetration of the air into the chamber in front of this opening;

0. The pressure of the gas.

The explosive combustible mixture, made by this first diffusion, thrown with violence or turbulence into the cone I3a of the second diffuser, takes with it a second quantity of air coming form the admission chamber of-the body 9.

A second diffusion is effected in the convergent cone I3a and a third in'the cone I319 into which penetrate, as previously, multiple streams of air drawn in through the grooves or slits It, the shape and gauging of which are determined according to the density of the combustible mixture to be diffused.

All these diifusions increasethe frequency of the explosions of the combustible mixture and, because of this, finally, the speed of flow and the explosive power are considerably increased so that in increasing the number of diffusionsone increases the reach of the final flame and'its tem perature.

One will notice that in the diffuser 53b, the

solid blades, separating the slots, guide the comlength. I The explosivemixture passing "through the central pipe I9 of this conformator is projected very far beyond the exit opening and explosions of great frequency are made at a distance ranging about 8 to 10 mm. from this opening, whilst the explosive mixture which passes with' retardment through the crown of openings at explodes at some millimetres from the exit which shapes the flame as represented in Figure 4.

It has been noticed that in spite of the explosions which are produced around the pipe I9, the temperature of the conformator I8l920 does not exceed 80 C. even after several hours working when the flame attains a temperature exceeding-13% (3., so that one can make this organ of ordinary metals such as brass.

When (Figures 1 and 5) one makes use of a cap 2|; the diameter of the exit opening, conical or straight, is determined by the power, the shape and the length of the flame to beproduced.

In the modification shown by Figure 6, certain parts of the apparatus of Figure l are incorporated and are designated by the same references.

The nozzle 5-'! discharges into the centre of a convergent cone 22, provided with a crown or concentric ring with openings 23, traversed by the peripheral air which passes between the tube 22 and the envelope 2d.

The cone '22 is followed by a divergent diffuser 25, a crown of openings 26 for the admission of peripheric air being arranged between these two parts. The diffuser 25 is followed in its turnby a convergent-divergent cone 2?, another crown ofopenings 23 being arranged between the parts 21.,and25 for another admission of peripheral air for diffusion.

The apparatus is finished by acap 29. In this apparatus there are thus-four successive diffusions.

The number of diffusers is moreover variable according to the temperature desired and the diametersof the openings and the conicities of the conduits are determined according to the density of the gases to be difiused.

In use, as in the preceding apparatus, the parts of the burner are cooled by the currents of air passing between the envelope and the various diffusers.

In everycase, with the apparatus of Figure l, as with. that of Figure 6, striking back of the name is impossible and the gas burns more perfectly and without any bad smell, this effect being all the more accentuated as the openings dividing the peripheral currents of air are more numerous.

- I claim: c

1. In a burner for lighting gasand other -combustible gases formingwith air an explosive mixture, a tubularenvelope, a gas nozzle protruding axially into the rear end of said envelope which is .formed with peripheral air admission apertures surroundingsaid gas nozzle, and a tubular diffuser mounted coaxially in said envelope with its open rear end facing said gas nozzle, said diffuser being spaced from said envelope so as to define therewith an annular chamber which is open at its rearxend, and, the frontend of said diffuser being in contact with said envelope and formedv with longitudinal islits connecting said annular chamber to the interior of said front end of the difiuser.

2. In a burner for lighting gas and other combustible gasesforming with air an explosive mixture, a tubular envelope formed at its rear end with, air admission apertures, a gas nozzle mounted in the rear end of saidenvelopecoaxially therewith, and a tubular diffuser mounted coaxially in said envelope in spaced relation thereto and with its open rear end facing said gas nozzle, the front end of said diffuser being in contact with said envelope, and said diffuser having a rear portion in the shape of an elongated convergin cone, and a front portion in the shape of a diverging cone merging into the inner wall of said envelope and formed with radial longitudinal slits connecting the annular space between said diffuser and said envelope to the interior of said front portion of the diffuser.

3. In a burner for lighting gas and other combustible gases forming with air an explosive mixture, a tubular envelope formed at its rear end with air admission apertures, a gas nozzle mounted in the rear end of said envelope coaxially therewith, a tubular diffuser mounted coaxially in said envelope in spaced relation thereto and with its open rear end facing said gas nozzle, the front end of said diffuser being in contact with said envelope, and said diffuser having a rear portion in the shape of an elongated converging cone, and a front portion in the shape of a diverging cone merging into the inner wall of said envelope and formed with longitudinal slits connecting the annular space between said difluser and said envelope to the interior of said front portion of the diffuser, and a static mixing member having a passage which is progressively restricted at its entrance and progressively enlarged at its outlet mounted in said envelope immediately behind said diffuser.

JEAN scHAFER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 329,776 Robertson et a1 Nov. 3, 1885 669,302 Franklin Mar. 5, 1901 715,300 Schaefer Dec. 9, 1902 799,424 Welch Sept, 12, 1905 1,104,017 Szocs July 21, 1914 1,177,027 Ferrier Mar. 28, 1916 1,205,265 Rosengren Nov. 21, 1916 1,357,351 Schurs Nov. 2, 1920 1,406,614 Corkell Feb. 14, 1922 1,948,737 Stettner Feb. 27, 1934 1,991,942 Kalk Feb. 19, 1935 2,008,130 Damm July 16, 1935 

